Slide 1Objectives
To understand how engineers use physics to set up a concert
Lighting
Electricity
Sound
Speaker
Sound-system
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Suggested narrative:
A microphone is used to turn the sound from artists voices and instruments in to electronic signals. They need to be converted to electronic signals because this allows them to be boosted to make them stronger.
Suggested activity:
Demo Microphone connected to CRO to show waveforms and conversion of sound to electronic signal.
Extension:
Sound-system
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Sound-system
The signal is turned back in to a (louder) sound by the speakers.
Ear
High pitch
Low pitch
High pitch
Low pitch
(i) which signal is from the loudest sound?
(ii) which signal is from the highest pitch sound?
Q1
120 dB or above can lead to instant hearing damage
Safe noise exposure
Suggested activity
http://www.youtube.com/watch?v=r1P6IQ5Wr_I&feature=player_embedded
Sound-speed
Sound travels to the audience at a speed of 330 m/s
Speed = distance ÷ time
Sound at a concert
The speed of sound is 330 m/s. How long it takes sound to travel 40 m?
Q2
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Red
Green
Blue
Cyan
Yellow
Magenta
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Lighting at a concert
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Lighting at a concert
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A red T-shirt absorbs green and blue and reflects red
Suggested activity [video]
Lighting at a concert
An artist on stage wears a red T-shirt with a yellow star motif, and blue trousers.
Complete the table showing how his costume appears under different colour lighting.
Q3
Making electricity
The electricity for outdoor concerts needs to be produced on-site using a generator.
Generator
Supplying electricity
Thick cables are used to carry large electrical currents to the sound and lighting systems.
Plug-in points for sound or lighting equipment
Generator
The larger the current, the thicker the cable needed.
The current in the cables can be calculated using the relationship
current = power ÷ voltage
Electrical current
A lamp with a power rating of 100 W. Calculate the current that flows when it is connected to a 240 V supply.
Q4
Electrical circuits
The lighting and sound systems are connected in parallel to the generators
Generator
Q5
Choose an artist
Each person in your team will take on a different role
But first you must choose the artist or group you will represent…
2 minutes
2 minutes
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Practice your skills
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Sound Engineer
Electrical Engineer
Lighting Engineer
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Check the card to see what your artist has requested.
Satellite speaker